textproduct: Quad Cities

KEY MESSAGES

- Heat and humidity will look to impact most of the area through the end of the week. The Heat Advisory has been expanded across the rest of the DVN CWA. If the advisory needs to be extended in time into Friday or beyond, then we would be into the longevity aspect of the heat which may require an upgrade to a warning for parts of the area.

- The Storm Prediction Center has a Marginal, level 1 out of 5, Risk for severe storms along and north of the Highway 20 corridor through tonight. Damaging winds are the primary risk.

- There is a near daily risk of showers and storms mainly for areas along and north of I-80. However, there will be plenty of dry hours.

UPDATE

Issued at 1257 PM CDT Tue Sep 1 2026

With higher sfc DPTs of mid to upper 70s pooling in the north closer to the boundary, have gone ahead and expanded the Heat Advisory acrs the rest of the DVN CWA. Some sites there in the new advisory area already well over a 100 degrees Heat Index.

SHORT TERM /THROUGH WEDNESDAY NIGHT/

Issued at 235 PM CDT Tue Sep 1 2026

Visible satellite imagery showing the "ring" nicely from NE all the way to WV. Quasi-stationary sfc boundary was noted along and just north of the CWA, with most progs suggesting it stay up there or even adjust a bit more northward through the night. Thus feel the local CWA will stay capped and hot through Wednesday with the fire of the ring occurring acrs MN and WI. Upper ridge placement and associated main short wave/MCV pathway will be up that way as well. Thus besides maybe a rogue elevated shower or weaker thunderstorm north of I-80 or even Hwy 30, feel the CWA will be mainly dry. The elevated shower chance may be higher late tonight and into mid Wed morning with a bout of nocturnal LLJ WAA. Will add patchy fog along and north of Hwy 30 after midnight in higher sfc DPT pool and closer to the sfc boundary where sfc winds may be more light and variable. Otherwise will bank on a persistent south to southwest sfc wind of 4- 7 MPH to keep widespread dense fog formation at bay. Overnight low temps in the low to mid 70s close to sfc DPT values.

On Wednesday and even into Wed night, again most of the convection (especially stronger storms) should be occurring mainly just to the north of the local CWA. That is unless a storm cluster with stronger cold pool mechanics can crash it's way further south than currently expected. Otherwise maybe just an isolated elevated shower or weak storm skirting acrs the northern CWA possible through Wed night. As for high temps, widespread low to mid 90s looks on target as long as we obtain enough insolation. That combined with ongoing low to mid 70 sfc DPTs supports the ongoing Heat Advisory.

LONG TERM /THURSDAY THROUGH MONDAY/

Issued at 235 PM CDT Tue Sep 1 2026

Thursday...Latest ensemble upper ridge placement and thermal gradient projections suggest another hot day of headline worthy heat, but also some upper ridge retrograde may be enough to allow for some convection to spill further southeast and possibly impact portions of the local fcst area especially Thu night into Friday morning. But that being said, some of the longer range CAMs such as the latest RRFS suggest bulk of the convection this day to occur to the north and east of the CWA. If organized storms/ clusters do manage to make it down this way, severe weather and damaging winds would be probable.

Friday...Depending on the potential for more storms down our way or at least convective debris and storm outflow, like the previous shift mentioned, this day may need an eventual heat headline. And if it does, the several days of high heat in a row rule may foster the need for an upgrade to an Extreme Heat Warning.

A look ahead to the upcoming weekend: Saturday could be a continuation of the hot humid weather and possible need of heat headlines, depending on storms and cloud debris. But then the heat may decrease by Sunday if we can get a backdoor style cool front from ridging acrs the western GRT LKS. This may be temporary with ensemble signs in the medium range runs of the heat dome trying to reestablish from the west and back acrs the region by mid next week.

AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/

Issued at 1257 PM CDT Tue Sep 1 2026

With the sfc boundary arching just to the north of the area, have gone with generally A VFR TAF fcst except for the DBQ site where being closer to the boundary may help the fog cause again there after midnight. Otherwise will bank on a persistent south to southwest sfc breeze of 4-6 KTs to keep VSBYs up at the rest of the sites, but may have to keep CID in mind for possible at least MVFR fog after 08z. DBQ and CID may also be suspect for isolated elevated showers or even a thunderstorm from this afternoon and into the overnight.

CLIMATE

Issued at 222 PM CDT Sun Aug 30 2026

Record Warm Low Temperatures:

September 1: KDBQ: 73/1937 KMLI: 75/1913

September 2: KDBQ: 74/2011 KMLI: 77/1913

September 3: KDBQ: 73/1939 KMLI: 76/1939

September 4: KDBQ: 71/1912 KMLI: 74/2018

DVN WATCHES/WARNINGS/ADVISORIES

IA...Heat Advisory until 7 PM CDT Thursday for IAZ040>042-051>054- 063>068-076>078-087>089-098-099. IL...Heat Advisory until 7 PM CDT Thursday for ILZ001-002-007-009- 015>018-024>026-034-035. MO...Heat Advisory until 7 PM CDT Thursday for MOZ009-010.